anestrum vs anoestrum

anestrum and anoestrum both are nouns.

Word	Noun	Adjective	Verb	Adverb
anestrum	Yes	No	No	No
anoestrum	Yes	No	No	No

As nouns, anestrum and anoestrum are synonyms defined as:

anestrum and anoestrum: applies to nonhuman mammals: a state or interval of sexual inactivity between two periods of estrus

Other synonyms of anestrum include anestrus, anoestrus.

anestrum (noun)	anoestrum (noun)
applies to nonhuman mammals: a state or interval of sexual inactivity between two periods of estrus	applies to nonhuman mammals: a state or interval of sexual inactivity between two periods of estrus